Convert Inch squared to Millidarcy

Convert Inch squared (in²) to Millidarcy (mD) instantly and accurately.

Inch squared (in²)
Millidarcy (mD)

Conversion Formula

mD = in² × 653708370000

About Inch squared

The square inch (in²) equals (0.0254 m)² = 6.4516 × 10⁻⁴ m² ≈ 6.54 × 10¹¹ D. An imperial area unit included for unit-conversion completeness; it appears in some US oil-country tubular goods and industrial filter-media specifications where flow cross-sections are stated in square inches. 1 in² ≈ 6.452 cm² = 6.4516 × 10⁻⁴ m².

About Millidarcy

The millidarcy (mD) equals 10⁻³ D ≈ 9.869 × 10⁻¹⁶ m², the everyday unit in petroleum reservoir engineering worldwide. Conventional sandstone reservoirs: 1-1 000 mD; carbonate reservoirs: 0.1-100 mD; economic gas recovery typically requires k ≥ 0.1 mD. Permeameter and well-test reports give results in mD. 1 mD = 10⁻³ D = 10³ µD.

Quick Reference Table

Inch squared (in²)Millidarcy (mD)
1 in²6.537 × 1011 mD
2 in²1.307 × 1012 mD
5 in²3.269 × 1012 mD
10 in²6.537 × 1012 mD
25 in²1.634 × 1013 mD
50 in²3.269 × 1013 mD
100 in²6.537 × 1013 mD

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